Merge branch 'Pr1' of https://github.com/romange/liburing

* 'Pr1' of https://github.com/romange/liburing:
  man/io_uring_prep_recv: expand on how to handle bundles

Author: axboe

man/io_uring_prep_recv.3

@@ -94,12 +94,18 @@ field indicates the total number of bytes received, and the buffer ID returned
 in the CQE
 .I flags
 field indicates the first buffer in the receive operation. The application must
-iterate from the indicated initial buffer ID and until all
+process the indicated initial buffer ID and until all
 .I res
 bytes have been seen to know which is the last buffer in the receive operation.
-The buffer IDs consumed will be contiguous from the starting ID, in the order
-in which they were added to the buffer ring used. Receiving in bundles can
-improve performance when more than one chunk of data is available to receive,
+The buffers consumed will be contiguous from the initial buffer, in the order
+in which they appear in the buffer ring. The CQE struct does not contain
+the position of the buffer in the buffer ring, therefore in order to identify
+buffers contained by the bundle, it is advised to maintain the cached head
+index per buffer ring. This uint16_t index represents the position of the next
+buffer to be consumed within the ring. Upon completion of a receive operation,
+the cached head index should be incremented accordingly.
+Receiving in bundles can improve performance when more than one chunk of
+data is available to receive,
 by eliminating redundant round trips through the networking stack. Receive
 bundles may be used by both single shot and multishot receive operations. Note
 that, internally, bundles rely on the networking stack passing back how much